1. Field of the Invention
One embodiment of the present invention relates to a touch sensor and a flexible touch sensor. Another embodiment of the present invention relates to a touch panel and a flexible touch panel. Another embodiment of the present invention relates to a touch panel module and a flexible touch panel module.
Note that one embodiment of the present invention is not limited to the above technical field. One embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. One embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Specific examples of the technical field of one embodiment of the present invention disclosed in this specification include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic device, a lighting device, an input device, an input/output device, a method for driving any of them, and a method for manufacturing any of them.
In this specification and the like, a semiconductor device generally means a device that can function by utilizing semiconductor characteristics. A semiconductor element such as a transistor, a semiconductor circuit, an arithmetic device, and a memory device are each an embodiment of a semiconductor device. An imaging device, a display device, a liquid crystal display device, a light-emitting device, an electro-optical device, a power generation device (including a thin film solar cell and an organic thin film solar cell), and an electronic device may each include a semiconductor device.
2. Description of the Related Art
A device where a display image can be changed by touching a display surface, that is, a device where a signal is input by touching the display surface has been recently known. The device is referred to as a touch panel. Providing a touch sensor to overlap a display portion for image display enables a user to operate an electronic device more intuitively. Examples of such an electronic device include a mobile phone, a smartphone, a personal computer, a tablet, a portable game console, and a portable music player.
There are various kinds of structures of touch panels. Specific examples of touch panel structures are a structure in which a display panel is provided with an external touch sensor for detecting an input signal, and a structure in which a display panel incorporates a touch sensor. Examples of a method for detecting an input signal include a resistive touch technology, a capacitive touch technology, and an optical touch technology. Examples of the structure in which a display panel incorporates a touch sensor include an in-cell touch panel and an on-cell touch panel. There is also an active matrix touch sensor including an active element such as a transistor.
For example, Patent Document 1 discloses an in-cell optical touch panel.